Study On Migration Dynamics Of Chemical Substances Of Plastic Packaging Materials During Microwave Treatment

As indirect food additives, food containers and packaging materials are closely correlative with food. They directly influence the food security and the health of people. During the microwave treatment, the additives and residual monomer in polymer quickly migrant into the contact food by the dynamics of diffusion, this endangers the people's health. Therefore, to study the experiment and theory of plastic packing material chemical's migration and find out the principle and dynamics of migration process during microwave are of important practical and theoretical significance.We studied the migration process of antioxidant 1076 from HDPE film into the fatty food simulants (olive oil, peanut oil, kurrajongs oil) through single contact. Here, different input power 100W,250,600W,900W were carried out by MWS OSR-8 (Canada, FISO Technologies). Real time monitoring of the relationship between the temperatures of simulants and heating time was implemented by optical fiber temperature sensor system. Then, the migration amount of antioxidant 1076 into three different fatty food simulants was analyzed under different input powers by HPLC. The results show that, in the three different fatty food simulants, the migration processes are similar. Under the same input power, the longer the time is, the more amount of antioxidant of migration; at the same time, the bigger the input is, the more amount of antioxidant of migration.We built the diffusion coefficient model based on the semi-empirical formulary of diffuse coefficient of Brandsch. In the Brandsch model, the temperature T was substituted by the absorption power P and time t or the profile of temperature T and time t testing by the MWS OSR-8. Depending on the condition of food-packaging and Fick's second law, the solution of migration amount of contaminant was obtained with given initial and boundary conditions. The experimental data and the model value were compared to evaluate the model. Results demonstrate that the model can well predict trend of migration and rate too highly under experiment conditions, which is safety. Besides, we use the linear relationships between diffusion coefficients logDp and 1/T developed from migration experiments under normal temperatures regarding n-hexane, isooctane and 95% ethanol as the fat simulants and the profile of temperature and time under microwave to predict the migration quantity with the microwave action model. The experimental results show that the model can work well.